Stereoselective synthesis of alcohols, XL. Stereoselective cyclization of 7-oxo-2-heptenylboronates

Synthesis of γ-Boryl-Substituted Homoallylic Alcohols with anti Stereochemistry Based on a Double-Bond Transposition

The stereoselective synthesis of anti isomers of γ-boryl-substituted homoallylic alcohols is disclosed. (E)-1,2-Di(boryl)alk-1-enes undergo Ru-catalyzed double-bond transposition with control of the geometry. The in situ generated (E)-1,2-di(boryl)alk-2-enes add to aldehydes in a stereospecific manner. The alkenylboron group within the product is amenable to a variety of synthetic derivatizations.

Allylic borylation of tertiary allylic alcohols: a divergent and straightforward access to allylic boronates

A novel method for the preparation of diverse allylic boronates from simple allylic alcohols is reported.

Study of a Radical Cyclizations Cascade Leading to Bicyclo[3.1.1]heptanes

An efficient radical cascade involving a 5-exo-dig, a 1,6-H transfer, a 6-endo-trig, a 4-exo-dig, and a final 1,6-H transfer allows the diastereoselective construction of bicyclo[3.1.1]heptanes. The size of the R substituent at the propargylic position governs the diastereoselectivity of the 6-endo-trig step. Other parameters (acetylenic substituents, unsaturated partners,.) have been investigated, and the scope and the limitations of the cascade have been delineated.